According to foreign media reports, one day about 120000 years ago, in the Nefud desert of Saudi Arabia, some humans walked along an ancient lake. They may stop to drink fresh water or follow groups of elephants, wild donkeys and camels trampling on mudflats. After a few hours, however, human and animal footprints dried up and eventually became fossils. Today, these ancient footprints provide rare evidence of when and where early humans lived in the Arabian Peninsula. “These are the first real human footprints in the Arabian Peninsula,” said Michael Petraglia, an archaeologist and team leader at the Max Planck Institute for human history sciences. The Arabian Peninsula has been regarded as an obvious route for the early human beings to move out of Africa to the Middle East and Eurasia. Stone tools show that ancient humans explored the Arabian Peninsula at different times in prehistory. At that time, the climate was more humid and harsh, and the desert was green grassland dotted with freshwater lakes. But so far, researchers have only found a human phalanx 88000 years old, which proves that modern people lived there, rather than other ancient human tool makers. < p > < p > Petraglia and her international colleagues, after a decade long search of the Arabian Peninsula using satellite images and ground-based fact finding, have discovered tens of thousands of ancient freshwater lake beds, including one in Nefud called alathar. Note: alathar means “trace” in Arabic. There, researchers found hundreds of footprints on the heavily trampled surface of the lake bed, which had been exposed by recent erosion of sediment. It is understood that nearly 400 tracks have been left by the animals, including a wild donkey, a huge Buffalo, and some elephants and camels. Only seven of these footprints were identified as human footprints. But by comparing the size and shape of footprints left by modern humans and Neanderthals, the researchers concluded that the footprints were probably left by people with longer feet, higher stature and smaller weight, Homo sapiens, rather than Neanderthals. < / P > < p > the researchers point out that the age of the sediments also indicates that these footprints were left by Homo sapiens. The team used a method called light stimulated cold light, and then measured the electrons to infer the time when the sediments were last exposed to light, and finally determined that the upper and lower limits of the lower footprints were 121000 and 112000 years, respectively. < / P > < p > at the time, “Neanderthals were not yet present in Levant (Middle East),” said Matthew Stewart of the Max Planck Institute of chemical ecology, co-author of the paper. “So we think these footprints may be Homo sapiens.” < / P > < p > however, it depends largely on the age. Geochronologist Bert Roberts of the University of Wollongong noted that there were some uncertainties in the dating of the site, including the age of the animal fossils, the potential problems in calculating the precise decay rate of uranium in sediments, and so on. Marta mirazon Lahr, a paleoanthropologist at Cambridge University, also said the team could not completely exclude Neanderthals because the fossil record in Arabia is very fragmented. She’s more likely to be a candidate. Global Tech